Journal of Stem Cells & Regenerative Medicine最新文献

Introduction: Various therapeutic materials such as hyaluronic acid (HA) and platelet-rich fibrin lysate (PRF-L) have been represented to improve chronic fibroblast ulcers and premature aging. HA crosslinking is the most popular dermal filler presently in the therapy of aging skin. With the PRF-L properties that are rich in growth factors (GF), the combination of these materials is expected to produce synergistic and potentiation effects. Objective: This study aimed to determine the effect of various degrees of HA crosslinking on GF levels in PRF-L. Materials and Methods: PRF-L was obtained from PRF of healthy adult venous blood with 72 hours of incubation. HA was taken from preparations with 3 crosslinking degrees of 3%, 4%, and 10%. Measurement of GF levels was performed using sandwich ELISA method. Results: The GF levels released in PRF-L increased with the addition of HA crosslinking. The lower HA crosslinking degree (3%) triggered greater release of GF by PRF-L compared to higher HA crosslinking degree (4% & 10%). Conclusion: Low degree HA crosslinking elevated all measured GF levels in PRF-L. The lower HA crosslinking degree provoked higher release of GF.

Objective: Mesenchymal stem cells (MSCs) have been isolated from various human tissues. Although they share cardinal stem cell features of self-renewal and multi-potency, they also seem to possess distinct characteristics depending on the tissue types they originated from. When developing stem cell-based therapies, MSCs with the most desirable characteristics should be chosen. However, our knowledge on tissue type-specific characteristics of MSCs is limited. Here, we comparatively studied the gene expression profiles of MSCs from different tissue types, and predicted target diseases suitable for each type of MSCs. Methods: We harvested MSCs from human dental pulp and adipose tissue specimens and subjected them to gene expression microarray analysis. Characteristic gene expression signatures of the MSCs from each tissue type were identified using gene-annotation enrichment analysis. Results: Dental pulp-derived MSCs exhibited gene expression signatures of neuronal growth, while adipose tissue-derived MSCs exhibited signatures of angiogenesis and hair growth. MSCs from each tissue type expressed a discrete set of genes encoding secretory peptides, which may function as paracrine factors. Conclusions: MSCs derived from different tissue types demonstrated distinct gene expression signatures, which are suggestive of target diseases in clinical applications of the MSCs and stem cell-conditioned media. By expanding the analysis to MSCs from a wide range of tissue types, and by employing multiple omics approaches, a catalogue of MSCs and therapeutic targets can be generated.

AIM: Huntington's disease (HD) is an inherited disease caused by an expansion of cytosine-adenine-guanine (CAG) repeats in the huntingtin gene (HTT) that ultimately leads to neurodegeneration. To study the molecular basis of this disease, induced pluripotent stem cells (iPSCs) generated from patients' fibroblasts were used to investigate axonal mitochondrial trafficking and the nature of nuclear indentations. METHODS: Pathological and control iPSCs generated from patients with a low number of repeats were differentiated in striatal neurons of the brain. Mitochondrial density was measured along the axon using tubulin beta 3 co-staining in pathological and control neurons. To investigate the connection of nuclear roundness with calcium dysregulation, several calcium inhibitors were used. Proteasome system inhibition was applied to mimic premature neuronal ageing. RESULTS: We found that the mitochondrial density was approximately 7.6 ± 0.2 in neurites in control neurons but was only 5.3 ± 0.2 in mutant neurons with 40-44 CAG repeats (p-value <0.005). Neuronal ageing induced by proteasome inhibitor MG132 significantly decreased the mitochondrial density by 15% and 25% in control and mutant neurons to 6.5 ± 0.1 (p-value < 0.005) and 4.0 ± 0.3 (p-value < 0.005), respectively. Thus, for the first time, an impairment of mitochondrial trafficking in pathological neurons with endogenous mutant huntingtin was demonstrated. We found that inhibiting the sarco/endoplasmic reticulum Ca2+-ATPase (SERCA), the ryanodine-receptor (RyR) or the inositol 1,4,5-trisphosphate receptor (IP3R) by specific inhibitors did not specifically affect the nuclear roundness or survival of pathological neurons differentiated from patient iPSCs. Therefore, nuclear calcium homeostasis is not directly associated with HD pathology. CONCLUSION: Identifying HD iPSCs and differentiating from them neurons provide a unique system for modelling the disease in vitro. Impairments of mitochondrial trafficking and nuclear roundness manifest long before the disease onset, while premature neuronal ageing enhances differences in mitochondrial distribution.

Background: The objective of this study is to assess if infusion of osteoblasts can temporarily reverse osteoporosis in rats. Methods: Osteoporosis was induced in 20 female Sprague-Dawley rats by performing ovariectomy (OVX) that was carried out at 4 weeks of age. At 3 months a biopsy of the iliac crest was made to assess the bone quality and the same site bone marrow was harvested. From the bone marrow aspirate, MSCs were separated. Osteoblasts were then generated and were characterized using Alizarin red staining. Osteoblasts were injected in the tail vein of 10 rats. Two weeks after the injection of osteoblasts, a second biopsy was done. Animals were euthanized after 8 weeks of osteoblasts infusion by overdose of ketamine mixed with xylazine. The whole femurs and lumbar spine were dissected and the specimens were stored in 2% formalin. The specimens were analyzed using HRpQCT (High-resolution peripheral quantitative computerized tomography (μCT 100, SCANCO Medical AG, Brüttisellen, Switzerland). Results: In all the 10 animals from which bone aspiration was performed, osteoblasts were cultured and transplanted. Analysis showed that there was significant bone formation at bone sites of distal femur and lumbar spine (<0.001), with increased number of trabeculae and thickness (P<0.001). Further analysis revealed that there was robust bone formation in the animals that had osteoblasts injection. Conclusions: This preliminary study indicates that osteoblasts infusion can lead to new bone formation in osteoporosis induced by ovariectomy in rats.

Stem cell research for treating or curing ischemic heart disease has, to date, culminated in identifying which scenario is more important; 1) stem cell differentiation into cardiomyocytes that integrate electrically with the heart, 2) stem cells that secrete paracrine factors that promote healing, or 3) a combination of both. We consistently found that unipotent germline stem cells, when removed from their niche and cultured in the correct medium endogenously express pluripotency genes, which induce them to become human germline pluripotent stem cells (hgPSCs). These cells are then capable of producing cell types from all three germ layers. Using hgPSCs along with a modified version of a relatively novel cell-expansion culture methodology to induce quick, indefinite expansion of normally slow growing hgPSCs, it was possible to test the potential of cardiomyocytes derived from hgPSCs for treating an ischemic cardiac event. Upon differentiation into cardiac lineages, our data consistently showed that they not only express cardiac genes, but also express cardiac-promoting paracrine factors. Taking these data a step further, we found that hgPSC-derived cardiac cells can integrate into cardiac tissue in vivo. Note, while the work presented here was based on testes-derived hgPSCs, data from other laboratories have shown that ovaries contain very similar types of stem cells that can give rise to hgPSCs. As a result, hgPSCs should be considered a viable option for eventual use in patients, male or female, with ischemic heart disease.